Aircraft Design - Landing Gear and Subsystems Quiz(MCQ)

1 .

Following diagram represents ______

A)

bicycle

B)

tricycle

C)

quadruple

D)

tail dragger

Correct Answer : bicycle

Explaination : Typical bicycle landing gear arrangement is shown in the above diagram. As shown in the diagram, bicycle arrangement has 2 main landing gear and small outrigger wheels. It requires flat attitude for operation.

2 .

An aircraft is supported by bicycle landing gear arrangement. If wheel base is 10 unit then, scale location of CG.

A)

5 unit aft from front wheel

B)

10 unit

C)

20 unit from front wheel

D)

25 unit from back wheel

Correct Answer : 5 unit aft from front wheel

Explanation : Typically, for bicycle landing gear CG is aft of the midpoint between two wheels measured from front wheel.
Hence, Location of CG = distance/2 = 10/2 = 5 unit aft from front wheel.

3 .

What is tipback angle?

A)

Lift to drag ratio

B)

Wing loading divided by span

C)

Maximum altitude of an aircraft

D)

Maximum attitude of an aircraft with tail touching the ground with struts fully extended

Correct Answer : Maximum attitude of an aircraft with tail touching the ground with struts fully extended

Explanation : Tipback angle is defined as Maximum attitude of an aircraft with tail touching the ground and the struts are completely extended. Wing loading is the ratio of weight and reference area. Lift to drag ratio is called aerodynamic efficiency.

4 .

Following diagram represents _____

A)

bicycle

B)

tail dragger

C)

tricycle

D)

single main

Correct Answer : tail dragger

Explaination : Above diagram is representing a typical tail dragger landing gear arrangement. As shown in the diagram, tail dragger configuration has two main gears located ahead of cg. It also includes an auxiliary wheel at tail as shown in the diagram.

5 .

Following diagram represents _______

A)

bicycle

B)

tail pusher

C)

quadric cycle

D)

tricycle

Correct Answer : tricycle

Explaination : Typical tricycle landing gear arrangement is shown in the above diagram. As shown in the diagram, two main landing gears are located after the c.g. It has an auxiliary third wheel which is placed forward of the centre of gravity.

6 .

Following diagram represents ________

A)

wing

B)

multi bogey

C)

bicycle

D)

pusher prop

Correct Answer : multi bogey

Explaination : Above diagram is illustrating a typical multi- bogey landing gear arrangement. As shown in the diagram, multi bogey arrangement has more than 4 wheels to support higher impact loads and to carry heavy structure. Pusher prop is type of engine propulsion system.

7 .

Typically, an aircraft weighing lower than 50000 lb will adopt _________

A)

bicycle

B)

tricycle

C)

tail dragger

D)

single main gear

Correct Answer : single main gear

Explanation : Given, weight W = 50000 lb. If weight w < 50000 lb then, the single main landing gear arrangement is used. Other arrangements are used if weight w is > 50000 lb.

8 .

Following diagram represents _____

A)

wing lofting

B)

empennage section

C)

thrust loading chart

D)

single main landing gear arrangement

Correct Answer : single main landing gear arrangement

Explaination : Above diagram is showing typical single main landing gear arrangement. Lofting is used to generate overall wing shape via conic lofting method. Empennage is tail portion of the aircraft. Thrust loading is defined as thrust to weight ratio.

9 .

What is the location of main wheel in tricycle gear?

A)

At CG

B)

At nose

C)

Before CG

D)

After CG of the aircraft

Correct Answer : After CG of the aircraft

Explanation : Main wheel is located after the cg of the aircraft in typical tricycle landing gear arrangement. This arrangement is stable. An auxiliary wheel is located ahead of cg of the aircraft. It can be used for large crab angle as well.

10 .

Which of the following is disadvantage of tail dragger?

A)

Most stable

B)

Inherent unstable

C)

Inherent stable

D)

It has 4 wheels to support the aircraft

Correct Answer : Inherent unstable

Explanation : Tail dragger arrangement consists total of 3 wheels: 2 main and 1 auxiliary. Tail dragger arrangement is inherently Unstable. Tail dragger arrangement provides more propeller clearance and it is lighter in weight.

11 .

The term marked by ‘?’ in the following diagram is called _______

A)

AOA

B)

Overturn angle

C)

Grazing angle

D)

Overnose angle

Correct Answer : Overturn angle

Explaination : The term marked is called overturn angle. It is measure of the tendency to overturn during taxied around sharp corner. For typical aircrafts this should not be more than 63°. AOA is angle between relative freestream velocity and chord.

12 .

Following diagram represents ________

A)

lift curve

B)

drag polar

C)

drag curve slope

D)

wheel diameter for braking

Correct Answer : wheel diameter for braking

Explaination : Above figure is used for initial and statistical estimation of required wheel rim diameter. This estimation is based on kinetic energy absorption at the time of braking. Lift curve represents relationship between lift and AOA.

13 .

If tire pressure is 25 psi then, determine minimum dynamic hydroplaning speed.

A)

25 knots

B)

45 knots

C)

369 knot

D)

25 psi

Correct Answer : 45 knots

Explanation : Given, tire pressure p = 25 psi
Minimum dynamic hydroplaning speed V can be estimated by using,
V = 9*p^0.5 = 9*25^0.5 = 9*5 = 45 knots.

14 .

An aircraft is designed to have landing weight of 2500N and stall speed V of 9.8m/s. How much kinetic energy should be absorbed by wheel? Consider number of wheels with brake is 2.

A)

6125J

B)

235 KJ

C)

5.98 KJ

D)

2100

Correct Answer : 6125J

Explaination : Given, landing weight W = 2500N, stall speed v = 9.8m/s. Number of wheels n = 2.
Kinetic energy K.E. = 0.5*W*v²/g*n = 0.5*2500*9.8²/9.81*2 = 6125 J

15 .

A general aviation aircraft has impact Weight on wheel about 100 unit. Find the required diameter.

A)

7.53 unit

B)

9.753 unit

C)

10.98 unit

D)

11 unit

Correct Answer : 7.53 unit

Explanation : Given, Weight on wheel W = 100 unit.
For, general aviation aircraft Diameter D = 1.51*W0.349 = 1.51*100^0.349 = 7.53 unit.

16 .

Evaluate width of the wheel if weight carried by it is 200 unit. Consider general aviation aircraft.

A)

9/7 unit

B)

9 unit

C)

7 unit

D)

3.73 unit

Correct Answer : 3.73 unit

Explanation : Given, Weight W = 200 unit
Width of general aviation is given by,
Width w = 0.715*W^0.312 = 0.715*200^0.312 = 3.73 unit.

17 .

A bomber aircraft has following data. Weight on wheel is 80 unit. Calculate the width of main wheel.

A)

3.45

B)

6.78

C)

0.8546

D)

0.2345

Correct Answer : 0.8546

Explanation : For bomber, weight W = 80 unit.
Width of main wheel d = 0.1043*W^0.48 = 0.1043*80^0.48 = 0.8546 unit.

18 .

What is the function of the undercarriage?

A)

To provide lift

B)

To carry cargo at airport

C)

To absorb the shock during landing

D)

To increase lift at landing

Correct Answer : To absorb the shock during landing

Explanation : Undercarriage should absorb the shock or impact during landing and make ride smooth during taxiing. Lift is primarily generated by wings. Lift can be increased by high lift devices. Cargo container is used to carry cargo.

19 .

Which of the following is an example of a shock absorber?

A)

Flap

B)

Elevator

C)

Lift curve slope

D)

Solid spring shock arrangement

Correct Answer : Solid spring shock arrangement

Explanation : Solid spring shock arrangement is an example of shock absorber. Lift curve slope is defined as change in lift by change in alpha. Flap is secondary control surface.

20 .

Stroke depends on ________

A)

rate of climb

B)

vertical velocity at touchdown

C)

lift by wing at cruise

D)

vertical velocity at climb

Correct Answer : vertical velocity at touchdown

Explanation : Stroke is defined as the amount of deflection required by shock absorbing system. Deflection required by shock absorber depends upon number of parameters. For example, vertical velocity at touchdown is one of the important factor affecting the stroke of the shock absorber. Lift at cruise will be same as weight at cruise.

21 .

If piston diameter of an oleo system is given by 20 unit then, find the approximate value of typical external diameter of the same oleo system.

A)

10 unit

B)

26 unit

C)

50 unit

D)

200 unit

Correct Answer : 26 unit

Explanation : Approximate value of external diameter can be given by,
D = piston diameter + 0.3* piston diameter
= 20 + 0.3*20 = 26 unit.

22 .

If an aircraft has sink speed at touchdown as 9 ft/s then, find the stroke in inches approximately.

A)

1 in

B)

2 in

C)

9 in

D)

19 in

Correct Answer : 9 in

Explanation : Given, sink speed = 9 fps.
Required stroke in inch = vertical or sink speed = 9 inch.

23 .

Following diagram represents _________

A)

drag polar

B)

wheel track only

C)

wheel base distance only

D)

simple oleo schematic

Correct Answer : simple oleo schematic

Explaination : A typical oleo mechanism is shown in the diagram. Simple oleo system has been illustrated in the figure. Drag polar is graphical representation of drag characteristics. Wheel track and base distance are related to wheel terminology not to shock absorber.

24 .

Which type of shock absorber is most widely used nowadays?

A)

Oleo

B)

Signal beam type

C)

Aurora beam type

D)

Longerons type always

Correct Answer : Oleo

Explanation : Oleo type shock absorber is widely used shock absorber. Longerons are structural elements of the aircraft. They are straight and heavy. They are lesser in number and opposes the bending.

25 .

Stroke of a shock absorber is defined as _______

A)

lift required at takeoff

B)

length of crank shaft of engine

C)

piston distance travelled inside engine

D)

required deflection of the shock absorbing system

Correct Answer : required deflection of the shock absorbing system

Explanation : Stroke of absorber can be defined as the required deflection of the shock absorbing system. Stroke of the shock absorber depends upon number of factors such as shock absorbing material etc. Lift required at takeoff will be more than its weight.

26 .

Following diagram represents ______

A)

cockpit

B)

tail Podded

C)

in the wing gear retraction

D)

cargo containers

Correct Answer : in the wing gear retraction

Explaination : As shown in figure, a typical gear retraction geometry is shown. As shown in the figure, gear is retracted inside the wing. Hence, it is called in the wing retraction geometry. Cockpit is front section of an aircraft through where pilot controls the aircraft.

27 .

Following diagram represents ______

A)

wing podded retraction

B)

lift curve

C)

tail plane retraction

D)

fuselage podded retraction

Correct Answer : wing podded retraction

Explaination : A typical wing podded gear retraction is shown in the diagram. Fuselage Podded will not be retracted inside wing. Lift curve is used to represent relationship between lift and angle of attack. Lift curve is very important parameter.

28 .

Following diagram represents ____

A)

headroom

B)

in the fuselage gear retraction

C)

in wing retraction

D)

retraction in cockpit

Correct Answer : in the fuselage gear retraction

Explaination : Typical gear retraction in the Fuselage is shown in the above diagram. It is similar to in the wing retraction geometry with difference being in the location of retraction. Here, gear will be retracted in the fuselage itself. Headroom is related to passenger cabin.

29 .

Following diagram represents ______

A)

drag polar

B)

in cockpit

C)

gear load chart

D)

gear retraction geometry

Correct Answer : gear retraction geometry

Explaination : Landing gear retraction is one of the important factor of landing gear design. Typical gear retraction geometry is shown in the above diagram. As shown in the diagram undercarriage is retracted inside the wing fuselage junction.

30 .

Following diagram represents ______

A)

gear retraction in fuselage

B)

gear retraction at wing tip

C)

gear retraction geometry in the nacelle

D)

gear retraction in wing fuselage junction

Correct Answer : gear retraction geometry in the nacelle

Explaination : Typical, gear retraction inside the nacelle is shown in the diagram. This type of arrangement can be seen in early prop aircraft. Gear retraction in fuselage or wing fuselage junction are nearly similar to each other.

31 .

Following diagram represents ______

A)

tail tip podded

B)

thrust required

C)

wingtip retraction

D)

typical fuselage Podded retraction

Correct Answer : typical fuselage Podded retraction

Explaination : Above diagram is representing the typical layout of fuselage Podded retraction geometry. Here, landing gear will be retracted inside the fuselage section of the aircraft. Thrust required will be based on operating conditions. At cruise, thrust required is equal to drag.

32 .

Following diagram represents ___________

A)

drag polar

B)

lift augmentation

C)

sliding pivot mechanism

D)

thrust augmentation

Correct Answer : sliding pivot mechanism

Explaination : The above figure is illustrating a typical sliding pivot mechanism. It is different from the typical four bar linkage system. Lift augmentation is used to increase lift. Thrust can be increased by thrust augmentation. Drag polar is graph showing relationship between drag and lift.

33 .

Following diagram represents _________

A)

pivot point estimation

B)

drag characteristics

C)

lift estimation via drag polar

D)

triangular curve mechanism

Correct Answer : pivot point estimation

Explaination : Above diagram is a simple schematic diagram illustrating the method to estimate the pivot point. Drag characteristics can be observed through numbers of graph for example, drag polar etc. Drag polar will be used to generate a typical drag property variation with respect to lift variation.

34 .

Drag brace is used to ________

A)

reduce drag

B)

withstand aerodynamic loads and breaking loads

C)

lowers the weight of an aircraft

D)

decrease the drag produced by gear only

Correct Answer : withstand aerodynamic loads and breaking loads

Explanation : Typical landing gear retraction arrangement includes a diagonal arm. This diagonal arm for nose wheel is called drag brace. Drag brace is used to withstand the breaking loads and aerodynamic loads as well.

35 .

Pivot point is defined as?

A)

CG of only quadric cycle gear

B)

The point with maximum lift to drag

C)

The point at which thrust forces is acting

D)

The point at which the landing gear leg is attached to the aircraft

Correct Answer : The point at which the landing gear leg is attached to the aircraft

Explanation : The point at which landing gear or undercarriage leg is attached to the aircraft is known as pivot point. This pivot point can be located anywhere along the normal bisector to the line joining the up and down wheel positions. Lift to drag will be maximum at thrust required minimum.

36 .

What is seaplane?

A)

Plane which can only land on water

B)

Plane which can only took off from water

C)

Plane which can land and takeoff from the water

D)

Seaplane is always same as any other plane in terms of landing and takeoff location

Correct Answer : Plane which can land and takeoff from the water

Explanation : Typical definition of a seaplane is as follows: plane which takes off from water and lands on water is known as a seaplane. Seaplanes are capable of landing and takeoff from water. Seaplanes are not necessarily same as other types of aircrafts.

37 .

If a seaplane needs to be designed then, which of the following could be considered as an application of the seaplane?

A)

Search and rescue mission

B)

Low value of wing loading

C)

Can be operated for every wave size in sea

D)

Ratio of weight to reference area is minimum among the other types of aircraft

Correct Answer : Search and rescue mission

Explanation : A typical seaplane can land and takeoff through water only. If we were given the task to design a seaplane then, one of the most applicable use of such plane would be for search and rescue. In fact, seaplanes are being used for such tasks. However, seaplanes cannot be used for every size of wave.

38 .

Following diagram represents _________

A)

mig29 design

B)

typical seaplane geometry

C)

typical aerostats

D)

schematic diagram of F16

Correct Answer : typical seaplane geometry

Explaination : A typical seaplane geometry is shown in the diagram. A seaplane is unique kind of plane which is capable of takeoff and land through water. F16 and Mig21 are fighter aircraft and are not seaplanes. Aerostats is different type of aircraft.

39 .

Most of the sea plane is designed with _______

A)

h bottom

B)

flat bottom only

C)

v shaped bottom only

D)

v shaped bottom

Correct Answer : v shaped bottom

Explanation : Most of the seaplanes are designed with V shaped bottom. The V shaped bottom can be used to reduce the water impact Loads. However, few seaplanes were built with flat bottoms also. Hence, correct option will be v shaped bottom.

40 .

For higher landing speed, deadrise angle should be ________

A)

lower

B)

higher

C)

lowest

D)

independent of speed

Correct Answer : higher

Explanation : Deadrise is defined as the height of V in v shaped bottom. The angle is called deadrise angle. Deadrise angle should increase for higher landing speed. Deadrise angle is increased towards the nose of the plane. Deadrise is dependent on speed also.

41 .

Which of the following is an example of seaplane?

A)

Voodoo

B)

A321 neo

C)

Curtiss NC

D)

Cessna 172

Correct Answer : Curtiss NC

Explanation : Curtiss NC is an example of seaplane. A321 neo is a commercial fixed wing aircraft that can only land or takeoff from the airfields. Cessna 172 is a prop aircraft that is not a seaplane.

42 .

Typically, seaplanes can be categorized as ________

A)

aerostats only

B)

flying boat only

C)

floatplanes only

D)

floatplanes, flying boat, etc

Correct Answer : floatplanes, flying boat, etc

Explanation : Typically, seaplanes can be divided as follows: Floatplanes, flying boat etc. Aerostats are type of aircraft. Aerostats are driven based on buoyancy. They are lighter than air vehicle. Typical seaplanes are categorized as heavier than air vehicle.

43 .

A seaplane has beam of 5 unit then, estimate the step size required for given seaplane.

A)

0.25 unit

B)

1.2 unit

C)

4.6 unit

D)

9 unit

Correct Answer : 0.25 unit

Explanation : Approximate value of step size = 0.05*beam = 0.05*5 = 0.25 unit.

44 .

Which of the following is an example of an aircraft subsystem?

A)

Landing gear

B)

Pneumatic

C)

High lift device

D)

Gear retraction

Correct Answer : Pneumatic

Explanation : Pneumatic system is an example of aircraft subsystem. Gear retraction refers to the method and configuration through which landing gears are retracted in the aircraft. Landing gear are used to withstand impact during landing.

45 .

Which of the following is considered to be correct subsystem to deflect control surface?

A)

Hydraulic system

B)

Fuel system

C)

Deice system

D)

Pneumatic subsystem

Correct Answer : Hydraulic system

Explanation : Hydraulic subsystem will be correct choice for control surface deflection. Pneumatic subsystem is used for low power or pressure requirements. Fuel system includes fuel tanks, fuel lines etc.

46 .

A pneumatic subsystem is used to ___________

A)

more pressure output

B)

deflect control surface

C)

provide electrical power

D)

provide compressed air for pressurization

Correct Answer : provide compressed air for pressurization

Explanation : A typical pneumatic system is used for operation requiring less amount of power or pressure. It is used to provide compressed air for pressurization of the aircraft. More pressure output can be achieved by using hydraulic system.

47 .

Following diagram represents ______

A)

Typical APU system at tail

B)

Fuel system

C)

Hydraulic system

D)

Thrust augmentation

Correct Answer : Typical APU system at tail

Explaination : APU is an example of subsystem of aircraft. Hydraulic system is used for higher output power. Thrust augmentation is used to increase the amount Thrust. Thrust augmentation can be used for short takeoff distance.

48 .

Let’s consider we need to design avionics system for general aviation aircraft. If empty weight of aircraft is 100 unit then what will be the approximate range of required avionics weight.

A)

0.3 to 0.5 units

B)

0.58 units

C)

1 unit to 3 unit

D)

4 to 5 units

Correct Answer : 1 unit to 3 unit

Explaination : Given, empty weight, W = 100 unit.
Typically, range of avionics weight can be estimated as follows.
Avionics weight range = 0.01*W to 0.03*W
= 0.01*100 to 0.03*100 = 1 unit – 3 unit.

49 .

A typical electrical system may include _____

A)

only generator

B)

only transformers

C)

drag polar system

D)

generators, transformers, cables, etc

Correct Answer : generators, transformers, cables, etc

Explanation : A typical electrical system consists of generators, transformers, cables etc. It is used to provide electrical energy. Drag polar is graphical representation of drag. It is used to show relationship between drag and lift.

50 .

Following diagram represents _______

A)

fuel tank location

B)

simplified hydraulic system

C)

pneumatic subsystem

D)

wing loading diagram

Correct Answer : simplified hydraulic system

Explaination : A typical hydraulic system is shown. A simplified hydraulic system can be observed in the diagram. As shown in the diagram a simplified hydraulic system includes actuators, feed lines etc. Fuel tank can be located in fuselage, in wing or in tail.

51 .

Hydraulic system affect conceptual design based on ______

A)

lift required at tail

B)

space for control surface

C)

hydraulic pump space requirements

D)

secondary control surface

Correct Answer : hydraulic pump space requirements

Explanation : A typical hydraulic system will affect conceptual design based on space requirements for pumps typically. Control surface are located at the wing or at tail section. Lift required at tail will be affected by which type of airfoil is used.